1. Field of the Invention
The present invention relates generally to a rear suspension system of a two wheeled pedal vehicle, such as a bicycle. More particularly, the invention relates to the mechanical function of a shock absorber which is an integral part of said suspension system.
2. Description of the Related Art
Bicycles of the type known as Mountain Bikes or ATB's (All Terrain Bicycle) are conventionally constructed in a rigid frame design. As one of the primary advantages of this type of bicycle is the ability to be ridden off-road, a comfortable ride is obviously desired. Rigid frame bicycles rely on special tires (wide cross section) and a small amount of natural flexibility in the frame and front forks to absorb somewhat the bumps of the road and trail. Adding rear suspension to the bicycle would substantially improve the smoothness of the ride.
However, a bicycle utilizing rear suspension one hundred percent of the time is not desirable. A rider, when pedaling hard for maximum power and efficiency, prefers a rigid frame whereby human energy output is vectored directly to the rotation of the rear wheel. It is an object of this invention to provide a frame design which incorporates both systems--rigid and suspended, allowing the rider to choose on demand which mode he prefers for that particular riding situation. The rider can switch back and forth instantly, such as by means of the actuation of a control lever on the handlebars, without dismounting from the bike or interrupting his pedaling cadence.